Experimental VF-1-derived client for the "Gemini" protocol
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Solderpunk 88daabe091 Overhaul TOFU checking code.
Main motivation for this was to switch from keying the cache cert
database off hostname + address to hostname + port.  While making
the necessary changes I refactored to reduce code duplication and
make the overall flow of the TOFU checks more transparent.

The check of whether the "previous certificate" has expired has
been changed from using the most frequently seen previous cert to
the most recently seen, which makes a *lot* more sense and is
arguably a bug fix.

The address column of the DB is now used only for reporting, but
the column is not maintained well, or rather, the semantics are
currently "address cert was first received from", and we may want
something less static?
2024-01-17 20:58:59 +01:00
src/av98 Overhaul TOFU checking code. 2024-01-17 20:58:59 +01:00
.gitignore Initial commit 2019-06-22 08:54:45 -04:00
LICENSE Fill out LICENSE template! Closes #17. 2020-06-04 20:29:03 +02:00
README.md Document RC files. Closes #27. 2020-12-24 13:27:18 +01:00
pyproject.toml Further splitting up and renaming of files. 2023-11-25 16:12:46 +01:00



AV-98 is an experimental client for the Gemini protocol. It is derived from the gopher client VF-1 by the same author. AV-98 is "experimental" in the sense that it may occasionally extend or deviate from the official Gemini specification for the purposes of, well, experimentation. Despite this, it is expected to be stable enough for regular daily use at the same time.


AV-98 has no "strict dependencies", i.e. it will run and work without anything else beyond the Python standard library. However, it will "opportunistically import" a few other libraries if they are available to offer an improved experience.

  • The ansiwrap library may result in neater display of text which makes use of ANSI escape codes to control colour.
  • The cryptography library will provide a better and slightly more secure experience when using the default TOFU certificate validation mode and is highly recommended.


  • TOFU or CA server certificate validation
  • Extensive client certificate support if an openssl binary is available
  • Ability to specify external handler programs for different MIME types
  • Gopher proxy support (e.g. for use with Agena)
  • Advanced navigation tools like tour and mark (as per VF-1)
  • Bookmarks
  • IPv6 support
  • Supports any character encoding recognised by Python

Lightning introduction

You use the go command to visit a URL, e.g. go gemini.circumlunar.space.

Links in Gemini documents are assigned numerical indices. Just type an index to follow that link.

If a Gemini document is too long to fit on your screen, use the less command to pipe it to the less pager.

Use the help command to learn about additional commands.

RC files

You can use an RC file to automatically run any sequence of valid AV-98 commands upon start up. This can be used to make settings controlled with the set or handler commanders persistent. You can also put a go command in your RC file to visit a "homepage" automatically on startup, or to pre-prepare a tour of your favourite Gemini sites.

The RC file should be called av98rc. AV-98 will look for it first in ~/.av98/ and second in ~/.config/av98/. Note that either directory might already exist even if you haven't created it manually, as AV-98 will, if necessary, create the directory itself the first time you save a bookmark (the bookmark file is saved in the same location). AV-98 will create ~/.config/av98 only if ~/.config/ already exists on your system, otherwise it will create ~/.av98/.